9 Cell Membrane And Transport Processes

Question 1

Active transport

Answer 1

Process where cells transport substances across a membrane from low to high concentration. This process consumes energy.

Question 2

Adhesion protein

Answer 2

A membrane protein that helps link cells together

Question 3

ATP

Answer 3

Adenosine triphosphate, a high energy compound, composed of adenine and ribose with three phosphate groups attached.
Function is to store usable energy for cellular reactions.

Question 4

Carrier protein

Answer 4

A protein within membranes that assists other molecules to cross the membrane. They can transport specific small molecules or ions against concentration gradient using ATP

Question 5

Cell membrane

Answer 5

Selectively permeable boundary of all living cells that maintains the contents of the salon regulates movement in an out

Question 6

Channel protein

Answer 6

A protein that forms channels within membranes to allow the passive passage of hydrophobic substances across the membrane. They catalyse movement of specific ions down the electrochemical gradient via passive transport, a process called facilitated diffusion.

Question 7

Cholesterol

Answer 7

A lipid embedded in cell membranes that provide stability and allows fluidity

Question 8

Concentration gradient

Answer 8

The difference in concentration of a substance between two different regions

Question 9

Contractile vacuole

Answer 9

The vacuole found in some freshwater unicellular organisms that maintain osmotic balance by collecting water, emptying it from the cell

Question 10

Cytoplasm

Answer 10

All the fluid dissolved materials and organelles between the cell membrane and the nuclear membrane

Question 11

Cytosol

Answer 11

The fluid part of cytoplasm containing highly organised fluid material and dissolve substances

Question 12

Diffusion

Answer 12

The passive movement of particles from a high to a low concentration of that substance

Question 13

Endocytosis

Answer 13

The movement of solids or liquids into a cell from the environment via vessel formation

Question 14

Enzyme

Answer 14

A biological catalyst that speeds up biological reactions without undergoing any change itself. Most enzymes are proteins.

Question 15

Equilibrium

Answer 15

Went to solutions have the same concentration of solutes, and the net movement is zero across a selectively permeable membrane

Question 16

Exocytosis

Answer 16

The movement of solids or liquids from inside the cell to outside the cell via vessel formation

Question 17

Extracellular fluid

Answer 17

The fluid that bass the outside of cells in multicellular organisms

Question 18

Facilitated diffusion

Answer 18

A form of diffusion that requires a substance to be attached to a specific carrier molecule to move across a membrane

Question 19

Falaccid

Answer 19

Floppy describes the condition of a plant cell that has lost water

Question 20

Fluid mosaic model

Answer 20

A model which describes membranes as a double layer of lipids, a lipid bilayer with the ability to flow and change shaped like a 2-D fluid. Special protein molecules are embedded in the leopard in various patterns like a mosaic.

Question 21

Hydrophilic VS hydrophobic

Answer 21

Hydrophilic is a substance that tends to interact with an dissolve in water, hydrophobic is a substance that avoids association with water

Question 22

Hypertonic Vs hypotonic

Answer 22

Hypertonic is a solution with a higher solute concentration compared with another solution, hypotonic has a lower solute concentration

Question 23

Ion

Answer 23

An atom or molecule that has an electrical charge due to losing or gaining electrons

Question 24

Isotonic

Answer 24

Two Solution with equal solute concentrations

Question 25

Net change

Answer 25

The amount of change after considering the movement of particles across a membrane in both directions. The result after subtracting movement in one direction from movement in the other is net change

Question 26

Osmosis

Answer 26

Movement of water across a selectively permeable membrane from regions of low salute. Concentration to high solute concentration

Question 27

Particle theory

Answer 27

Theory stating matter consists of tiny particles in constant motion, motion increases with higher energy

Question 28

Passive process

Answer 28

A process WITHOUT energy input

Question 29

Passive transport

Answer 29

Movement of molecules across the membrane WITHOUT energy input

Question 30

Phagocytosis

Answer 30

The bulk transport of solids into cell by engulfment and formation of vessels

Question 31

Pinocytosis

Answer 31

Bulk transport of liquids into a cell by engulfment and formation of vessels

Question 32

Plasmolsis

Answer 32

The cytoplasm pulling away from the cell wall, because of water loss from the cell

Question 33

Receptor proteins

Answer 33

A protein in a cell membrane that binds hormones and other signal molecules

Question 34

Recognition proteins

Answer 34

A protein the acts as a marker on membranes

Question 35

Selectively permeable

Answer 35

A membrane that allows some substances, but not others

Question 36

Sodium potassium pump

Answer 36

I membrane protein that uses energy to transport, sodium ions out of and potassium ions into sell against the concentration gradient

Question 37

Solute

Answer 37

A substance that can be dissolved in another

Question 38

Solution

Answer 38

Mixture of a solvent and solute

Question 39

Solvent

Answer 39

A substance in which another substance can be dissolved to create a solution

Question 40

Surface area to volume ratio

Answer 40

The mathematical ratio of the size of the surface area, compared to the volume of an object

Question 41

Tissue

Answer 41

A group of specialise cells working together to perform a specific function

Question 42

Transport protein

Answer 42

A protein that carries molecules across a membrane

Question 43

Turgid

Answer 43

Describes a salad that is tight and Richard from absorbing water

Question 44

What are cell membranes made of?

Answer 44

Hydrophilic head made of phosphate and glycerol with a hydrophobic tail made of saturated fatty acid and unsaturated fatty acid. these create a phospholipid bilayer.

Question 45

Functions of a cell membrane

Answer 45

- Recognition of other cells - Transporting materials - Providing attachment sites for enzymes and hormones - Enabling transmission of nervous impulses (in nerve cells )

Question 46

What is an amoeba?

Answer 46

A unicellular freshwater organism where the whole organism consist of a single cell. The amoeba can detect what is food, and what is silt in its pond

Question 47

Benefits of being multicellular

Answer 47

The cells in multicellular organisms are more protected from swings and environmental conditions because they are surrounded by extracellular fluid compared to single celled organisms.

Question 48

Who discovered cells

Answer 48

Robert Hooke and Anthony Van Leeuwenhoek described them in 17th century but in the 19th century scientist begin to understand them.

Question 49

Hoe did scientist know cell membranes were composed of lipids?

Answer 49

Charles Ernest Overton demonstrated that lipid soluble substances like ether and chloroform would enter cells suggesting they were composed of lipids

Question 50

What did Hugh Davson and James Danielli propose

Answer 50

The lipid bilayer was coated on either side with a layer of proteins. Another theory proposed by Gareth Nicolson said proteins penetrate through the phospholipid bilayer like a mosaic which better explains the physical and chemical properties. This was confirmed later with the invention of the electron microscope.